Turbine systems are continuously being modified to increase efficiency and decrease cost. One method for increasing the efficiency of a turbine system includes increasing the operating temperature of the turbine system. To increase the temperature, the turbine system must include components which can withstand such temperatures during continued use.
In addition to modifying component materials and coatings, one common method of increasing the temperature capability of a turbine component includes supplying a flow of cooling fluid. Often, to supply the cooling fluid flow, relatively cooler air is diverted from the compressor and provided to the component(s) to be cooled. In certain components, an impingement sleeve is positioned within the component, the impingement sleeve directing the cooler air towards an inner surface of the component.
Generally, impingement sleeves are open single plenum devices including a plurality of cooling holes formed therein. The cooler air fills the plenum of the impingement sleeve and then passes through the plurality of cooling holes. Typically, in order to control cooling flow from the impingement sleeve, the individual cooling hole count/size is changed to increase/decrease flows to certain zones. However, reducing cooling hole size can result in plugging while decreasing cooling hole count may reduce the effective coverage of the impingement cooling.
An article and method of forming an article that show one or more improvements in comparison to the prior art would be desirable in the art.